636490657 has 4 divisors (see below), whose sum is σ = 694353456. Its totient is φ = 578627860.

The previous prime is 636490619. The next prime is 636490711. The reversal of 636490657 is 756094636.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 636490657 - 2⁷ = 636490529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636490957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28931383 + ... + 28931404.

It is an arithmetic number, because the mean of its divisors is an integer number (173588364).

Almost surely, 2^636490657 is an apocalyptic number.

It is an amenable number.

636490657 is a deficient number, since it is larger than the sum of its proper divisors (57862799).

636490657 is a wasteful number, since it uses less digits than its factorization.

636490657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57862798.

The product of its (nonzero) digits is 816480, while the sum is 46.

The square root of 636490657 is about 25228.7664581525. The cubic root of 636490657 is about 860.1958527258.

The spelling of 636490657 in words is "six hundred thirty-six million, four hundred ninety thousand, six hundred fifty-seven".